Service

Problem

Cause

Solution

 

 

 

Fluid leaking from

a. Packing nut (4) loose.

a. Tighten, but not so tight as to grip

packing nut (4).

 

needle.

 

 

 

 

b. Packing (3-1, 3-2) worn or

b. Lubricate or replace.

 

dry.

 

 

 

 

Fluid nozzle (2)

a. Dry packing (3-1, 3-2).

a. Lubricate.

dripping.

 

 

b. Sluggish needle (10).

b. Clean and lubricate.

 

 

 

 

 

c. Packing nut (4) too tight.

c. Loosen.

 

 

 

 

d. Worn fluid nozzle or

d. Replace.

 

needle.

 

 

 

 

Thin, coarse finish.

a. Gun held too far from

a. Hold gun about 6 to 8 inches

 

surface.

(150 to 200 mm) from surface.

 

 

 

 

b. Atomization air pressure

b. Reduce air pressure.

 

set too high.

 

 

 

 

Thick, dimpled finish

Gun held too close to surface.

Hold gun about 6 to 8 inches

(resembling orange

 

(150 to 200 mm) from surface.

peel).

 

 

 

 

 

Service

3.Remove fluid adjustment knob (8-2) and spring (9).

4.Pull fluid needle (10) out the back of the gun.

Preparation

1.Flush and clean gun before servicing.

2.Follow Pressure Relief Procedure, page 5.

Air Cap, Nozzle, and Needle

1.Unscrew air cap (1).

2.Trigger gun while you remove the nozzle (2) with gun tool (27).

Trigger gun and use gun tool (27) when- ever you tighten or remove the nozzle (2) to avoid damage.

Air Valve and Needle Packings

1.Remove retaining rings (15), pin (16), and trigger (17).

2.Remove packing nut (4) and fluid needle packings (3-1, 3-2).

3.Remove fluid needle guide (7).

4.Remove fluid adjusting guide (8-1).

5.Remove spring (18) and air valve (19).

6.Remove air valve seat (20) and o-rings.

7.Replace parts as needed.

8.Assemble gun in reverse order. Lubricate needle and o-rings. Be sure to trigger gun when installing nozzle (2).

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Graco Inc 289238, 289240, 289242, 288890 Service, Preparation, Air Cap, Nozzle, and Needle, Air Valve and Needle Packings